Historical built-up intensity layer series for the U.S. 1810 - 2015

These files are part of the dataset "Historical built-up intensity layer series for the U.S. 1810 – 2015", contained in the dataverse “HISDAC-US: Historical Settlement Data Compilation for the United States” (https://dataverse.harvard.edu/dataverse/hisdacus). The BUI.tar.gz archive contains a time series if geospatial raster layers with pixel values representing the built-up intensity (BUI, i.e., the sum of indoor areas of all structures in that pixel) at 250m spatial resolution and 5 years temporal resolution. The other archives contain positional, thematic and temporal uncertainty layers (or raster series). The files are organized in .tar.gz archives. The readme file provides additional information. Data source: Zillow Transaction and Assessment Dataset (ZTRAX), Zillow Inc. -- Corrigendum: (1) In the original version 1.0 the unit for the BUI layers was described as square meters but the raster values were computed in square feet. This has been corrected in this new version and the raster values of all BUI layers are now correctly calculated in square meters; (2) The spatial reference system used to project the layers was incorrectly described in version 1.0. This has been corrected in this new version.

本文件属于数据集"1810-2015年美国历史建筑开发强度图层序列"，该数据集收录于哈佛数据文库（Dataverse）中的"HISDAC-US：美国历史定居点数据汇编"合集（https://dataverse.harvard.edu/dataverse/hisdacus）。其中BUI.tar.gz压缩包包含一套时空地理空间栅格图层序列，其像素值代表建筑开发强度（Built-up Intensity，简称BUI，即该像素内所有建筑物的室内面积总和），空间分辨率为250米，时间分辨率为5年。其余压缩包则包含位置、主题及时序不确定性图层（或栅格序列）。所有文件均以.tar.gz格式的压缩包进行封装，自述文件（readme）提供补充说明信息。数据来源：齐洛（Zillow）公司交易与评估数据集（Zillow Transaction and Assessment Dataset，简称ZTRAX）。勘误说明：（1）在1.0原始版本中，BUI图层的单位被标注为平方米，但实际栅格值是以平方英尺计算的。本新版本已修正该问题，所有BUI图层的栅格值现已正确以平方米为单位；（2）1.0版本中对图层投影所使用的空间参考系统描述有误，本新版本已完成修正。